For many years school busses have been provided with warning lights and other warning devices to stop traffic that may attempt to pass the bus in either direction.
U.S. Pat. No. 4,565,152, to Bennett shows an improvement upon the usual simple warning arrangements. Bennett employs a pivoted "stop sign" that swings out into view of oncoming traffic following which a flag is projected further outward (from the side of the bus) through a tube mounted on the stop sign when the latter is perpendicular to the side of the school bus. The flag and its support are not intended to provide a firm and strong barrier to oncoming traffic. Furthermore, the flag and its support would not substantially impair a driver intent on passing the bus. In another form, Bennett has a tube mounted horizontally across the front of the bus from which a rod may be extended outwardly to carry the flag and may later be retracted.